SQL trigger

I'm new to using triggers and have an assignment to add triggers to my database tables. Of coarse the person who asked me to do this is out of town, so I'm hoping someone can help.

This is what needs to be saved as the trigger (called trg_jrn_Org.sql):

if exists (select * from dbo.sysobjects where id = object_id('dbo.trg_jrn_Org') and OBJECTPROPERTY(id, 'IsTrigger') = 1)
drop trigger dbo.trg_jrn_Org
GO

CREATE TRIGGER trg_jrn_Org ON dbo.Org
FOR UPDATE
AS
BEGIN
UPDATE org
SET jrn_dt = GETDATE()
, jrn_host_nm = HOST_NAME()
, jrn_app_nm = APP_NAME()
WHERE org_id IN (SELECT org_id FROM INSERTED)
END

GO

So do I save this as a sep. file? or does all of this go directly into the trigger properties text area and replaces this:

CREATE TRIGGER [TRIGGER NAME] ON [dbo].[Wkly_Rprt]
FOR INSERT, UPDATE, DELETE
AS


or something else?

That's the whole code. It will create the trigger. Just go into iSQL and paste it and run it. You can see all your triggers by using Enterprise Manager. Right-click the table and choose All Tasks -> Triggers, then choose the type of trigger from the drop-down menu... there are only three: delete, insert, and update.
-Dave